Field of the Invention
The present invention is related to a heat dissipating fan, in particular, to a fan impeller with a stacked fan blade assembly.
Description of Related Art
The heat dissipating fans nowadays can mostly be categorized into two structural types of one type having blades integrally formed with a fan hub and the other type having metal stamping blades.
The first type of the structure having the blades integrally formed with the fan hub is simple and the manufacturing process is also relatively simple; therefore, it can be manufactured into a thin heat dissipating fan of a small size. The smallest allowable thickness of the blades of such structure is limited by the strength of the plastic structure and the technical level of the injection molding manufacturing process. Such type of structure cannot be arranged with more blades within a limited space; consequently, it is limited by the level of the manufacturing process such that it cannot be further improved to enhance its performance.
The second type of the structure having metal stamping formed blades can be manufactured to have relatively thinner blades; however, the stamped material is limited by the space in the horizontal plane. As a result, when there is a need to increase the number of blades, if all of the blades are to be integrally made as one single piece, then the width of the blade must be reduced correspondingly; if there is a need for a larger blade width, then each single blade must be formed by stamping individually. Consequently, it requires a higher manufacturing cost to use the method of manufacturing each single blade individually followed by the assembly in order to satisfy the need for densely arranging wide blades together.
In view of the above, the inventor seeks to overcome the problems associated with the currently existing technique after years of research and development along with the utilization of theoretical principles, and it is an objective of the inventor to provide a reasonable design and an improvement capable of effectively solve the aforementioned problems.